Consolidated statements of comprehensive income (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Net income	$ 362	$ 265
Available-for-sale investments:
Unrealized gains (losses), net of taxes	0	2
Net actuarial gains (losses) of defined benefit plans:
Adjustment, net of taxes	32	23
Reclassification of recognized transactions, net of taxes	17	11
Prior service cost of defined benefit plans:
Adjustment, net of taxes	(1)	(1)
Change in fair value of derivative instrument, net of taxes	1	(1)
Other comprehensive income (loss), net of taxes	49	34
Total comprehensive income	$ 411	$ 299

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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